Why Power Cables Affect Sound

I used one of these to find a nasty noisy switching trickle charger on my car in the garage:
https://www.amazon.com/gp/product/B001HX4D84/ref=ppx_yo_dt_b_asin_title_o04__o00_s00?ie=UTF8&psc=1

Obviously, the simplest solution is to keep power cords away from cables. Problem solved!
Of course, the real question is, is shielding on power cords per se bad for the sound, all things being equal? Apparently, shielding can affect the Sound when used for speaker cables and interconnects. Why not for power cords?

Mr. Smarty Pants, shielding on power cords doesn’t actually do anything when the rf is coming in on the conductor along with the current. Hel-loo!

The primary psychological phenomenon appears to be that naysayers have psyched themselves out.

I agree with the statement " I feel a well shielded power cable is more than adequate" However Geoff would have you strip off that pesky shielding to free the music hidden inside the (directional) cable. 

Thanks for sharing your experience @twinterfinder

‘Keeping an open mind goes a long way. Something that “prove it to me” folks should try and find out for themselves 

How many hallelujah moments can this thread sustain? 
There are so many amens lately that I feel like I'm in some old fashioned tent revival.

@elizabeth:

And that happens sometimes, doesn’t it? But note how it still doesn’t get us off the slippery slope of G.A.S. because we are addicted to our own positive reinforcements (adrenalin, endorphins) and will keep trying until we get our "fix." Also, there are times when something is inferior and we do something about it, and that, too, is positive reinforcement. One way or the other, we feed our addictions. We’re hard wired to do so.

I still think the technical reason for some power cables sounding better than others is reduction of noise floor and/or rejection of RF and other EM garbage.

I have had problems with overly BRIGHT aftermarket power cables. So I went back to the Belden cable that came with the amplifier and the sound became smoother and less harsh. I feel a well shielded power cable is more than adequate unless you have other issues with a component. Interconnects do have (IMO) more of an apparent effect on
sound quality, but I always find that the "fancier" the wire, the "more everything" comes out of the speakers.  Wire does not suppress the bad- it accentuates the good and the bad. And not by a mile, but perhaps a few yards. The quality of the recording is #1. #2 is the source component. And so on. The other end of the chain are your speakers.
Not forgetting your room of course. I auditioned a system in a mirror-filled room once and had to advise someone whether or not to buy a fairly decent pair of speakers. What could I tell him? The guy selling them used headphones anyway (!) What a joke. 

jetter852 posts01-20-2019 1:23pmGeoffkait (resident directionality guru), would you think that a manufacturer supplied power cable where the cable is made with the correct directionality would sound better or worse than a mega priced aftermarket PC made with the cable having the incorrect directionality but supposedly better construction/materials?

I have no idea. Too many variables. 😬

@jtucker: "If there is an audible difference, there should be a measurable difference ( and yes I agree that it may be possible that we don't know how to measure that difference yet )"

I agree there (eventually) should be electronically measurable differences, however, the human side of this difference engine is fraught with innumerable and uncontrolled psychological and physiologial variables, and that's where the real "measurement" problem lies.

Geoffkait (resident directionality guru), would you think that a manufacturer supplied power cable where the cable is made with the correct directionality would sound better or worse than a mega priced aftermarket PC made with the cable having the incorrect directionality but supposedly better construction/materials?

Calm down, people. Nobody measures anything. At least not power cords. Not much of anything else, either, I dare say. Certainly, not cables, not interconnects, not room treatments, not isolation devices, not sprays, enhancers, or any other tweaks. Give me a break! It doesn’t matter what to measure, it doesn’t matter what the measurements might be. This is all so hypothetical and irrelevant.

Elizabeth,Not necessarily disagreeing with you.  We might not be measuring the right characteristic that may or may not affect the perceived change in sound.  But why not measure the obvious things that most likely could affect sound?  If there was a measurable difference in ripple, noise, EMI or transient response, then that could put the naysayers to rest permanently.  If there is no measurable change, then you may be correct, we are just not looking in the right place.  If there is an audible difference, you should be able to measure some parameter, the trick may be in knowing what to look for.  Or maybe there is no difference...I'm not making any judgement on that one way or the other at this point.  I can't see why it would hurt to at least check some of the obvious characteristics.

@jtucker I like your idea. Let’s settle this thing once and for all and produce some measurements. It shouldn’t be hard to do given that the audibility is so apparent. I don’t know exactly what to measure but I would be inclined to look at transient behaviors instead of steady state properties. 

We have test equipment that can measure small differences in impedance and no they are not inexpensive.  My inquiry is not so much about the impedance of PCs but rather is there measurable difference in the quality of the plus and minus dc power rails of the end equipment or a measurable difference in the ac line (EMI) due between stock and aftermarket PC cables (looking in or looking out relative to the end equipment).  At this point, I don't even want to say whether or not it makes an audible difference.  I just want to know if it makes a measurable difference.  If you can see that there is a measurable change in noise / ripple /  EMI ( or some other quality ) then it follows that you  (may or may not) be able to hear it.  I think it would be interesting to do a comparison between a stock cable and an aftermarket cable under controlled conditions.  I am an EE that has worked in power for many years (disclaimer, not ac but dc/dc converters).  If there is an audible difference, there should be a measurable difference ( and yes I agree that it may be possible that we don't know how to measure that difference yet ).  Anyway , it would be interesting to me at least to look at the obvious characteristics like conducted EMI and PSRR.  Those differences would be easily explainable.  If there is anyone in the DFW area that is interested in doing some real (and unbaised) testing let me know.

I always find the people that say nothing makes a difference as bad as the green pen/snake oil crowd. I remember before Jitter was identified and measurable people thought those of us that had issues with CD's were nuts.

I’ve clearly heard differences in all sorts of cables over 30 years of being in audio. Just because you may not have or year read about some ABX test doesn’t mean others haven’t heard it.

I’ll take that action. Measure the resistance one direction, then the other. They are different. Scout’s honor. ✌️

Like I said, I'm not saying one way or the other whether you can hear a difference or not. Just curious to see if there are any measurable differences, even very subtle ones. Anyone else?

Excellent question. 

For me, I don’t think it’d be worth the expense though. If I was rich, I’d try it with good used power cables.

You don’t have to spend a ton. I got great improvement out of a $150 cable. I’m sure there is better stuff out there for more money but I was pleasantly surprised by that cable.

Like I said, I'm not saying one way or the other whether you can hear a difference or not.  Just curious to see if there are any measurable differences, even very subtle ones.  Anyone else?

It is astonishing such a large number of people looking for “real” and “measurable “ differences in cables and power cords. How about the good old fashioned listening? Like, with your ears? What’s wrong with that? 

Why so little trust to your ears guys? Why should one “prove” it to you with some graphs and measurements?

Against my better judgment, I am going to jump in here.  First off let me state that the stock power cables in my system have been replaced, but not with what any of you would consider "audiophile" PCs, just heavy duty equipment grade IEC cables.
There appear to be two ways to look at this, either as the PC being the last few feet of the delivery (looking into the component) or the first few feet (looking back out from the component.  Looking in, a well designed power supply should filter out any unwanted ripple or noise and looking out should prevent any unwanted ripple or EMI effects from going out to the hose wiring through the PC.  Equipment must pass the relevant EMI standards (FCC class B, etc)  It would be possible to measure the differences in conducted EMI using different PCs
Looking into the system, there are also relevant specifications that can be measured, such as PSRR (power supply rejection ratio), transient response and spectral content.  I am not saying one way or the other whether any of this is audible or not, but it would still be interesting to see if there is any real, measurable differences in performance between a standard IEC PC and an aftermarket high end cable.

I have access to extensive lab equipment and a shielded EMI chamber with conditioned AC source. Anyone in the DFW area interested in doing some comparison testing (you will have to supply the after market cable)?

There are people who would argue that power cords have a bigger impact than signal cables. I am unable to explain why, but they do

I was a cable skeptic back when. Then I visited my speakers for no reason other than geekerie. I was super surprised at the improvement. I definitely think signal cables make a difference.  I can’t see power cables doing anything though. It’s just bringing your 120/60 or what have you from the wall to your power supply. BUT, I do wonder if tiny tweaks like power cables and vibration control can add up to a positive cumulative effect?  For me, I don’t think it’d be worth the expense though. If I was rich, I’d try it with good used power cables. 

kosst,
I'm running an Aloia SS power amp, which I bought about a week and a half ago. This amp is in two pieces. One is the power supply which weighs about 80 pounds alone. The other piece is the amplifier portion. I believe it is very well engineered and it sounds wonderful. I initially put an inexpensive power cord on it (10 gauge) and listened to it for a few days, then put "my standard" aftermarket cable on it. Although not terribly expensive, it's an Oyaide Tunami cord, also 10 gauge. There was improvement in clarity top to bottom. Just my experience. 

Sometimes I hear a difference when replacing a power cord with another, sometimes I don’t. I sell the cable that don’t bring anything better to my system. I keep the one that does. Then repeat.

There are times where the difference is right off the bat, to the point of being wowed. There are times where the difference is subtle, if any. It takes many trials, and over the years as the system evolves. It’s fun.

If you never ever found any difference with your new multiple cables you have bought, there is a possibility you are buying the wrong cables. It's a possibility. I admit, it is difficult to determine what cable WILL make a difference good for you and what consists an upgrade from your current cable. It can only be found by trial and error.

One thing that I recommend you do, after getting a cable that does make a difference to you, regardless of the scale, is listen to your system with your new (better) cable for a week. Maybe just a good weekend. Then switch to the old cable. Are you missing anything? Then you will know.

I'm neither a skeptic nor a believer in power cables.  I'm listening to my system that has about $3K in after market power cables from several different manufacturers simply because I don't want to not have the best interface to power I can afford.  But, I never hear any difference in my system regardless of whether I'm using the equipment manufacturer's power cord or the after market power cord.

One of the problems with comparing before and after effects is the fact that you're relying on your memory for the base line and then attempting to find the difference in what you're now hearing.  Not a very good method of analysis.

One of the problems with using test equipment to measure differences is that you setup the equipment to find the differences you THINK you might find.  Instrumenting a test setup to find "everything" is difficult as you don't know what you're not looking for.

As an example, I had a custom built, image processing system in a VME rack and it was not working properly.  I traced the problem to the VME rack power supply.  I removed the power supply and took it in to the electronic engineers to be diagnosed.  They found nothing wrong with the power supply - correct voltage, correct amperage delivery, stability OK, etc.  So - they said "Nothing wrong with it."

I knew there had to be something wrong with it and went in to talk with software engineer who was also an electrical engineer.  He said, "I'll take a look at it."   About two hours later he said, "I've found the problem."  "There is a 250 KHz signal on the power."  "That signal is having a detrimental effect on one of the chip clocks and disrupting its processing."

So there you have it.  The EE's who originally looked at it had a fixed set of power supply problems in mind and verified their bias through testing for only what THEY thought could be a problem.  The person who found the problem decided to look at the QUALITY of the electrical output and used a completely different test method and equipment.

Then you get back to power cords, interconnects, and speaker cable - you have no "test instruments" other than your ears and memory - and you want to hear a difference.

I can hear differences in speaker types and designs, and can and have heard changes in my system when I change out certain pieces of equipment.  But cabling and power cords...I can't or don't hear any difference.

I don't hear a difference, but I'm willing to admit it may be my insensitivity to the change. So, I continue to make purchases of power cables and interconnecting cables with the hopes that I too will be "blown away" by the difference....only, so far, that's never happened.

Some people do hear a difference and that's okay. If it improves their listening experience that's really all that counts and makes the investment in the cables worthwhile.

kosst_amojan"This stuff makes NO technical sense"

What this really means is "I do not understand how this could possibly be useful, productive, or effective and therefore I will conclude, pronounce, and proclaim that it is useless because as an Expert on this forum it is for me alone to decide, determine, and establish the value, worth, and benefit of every aspect of Music Reproduction Systems and if you doubt, question, or challenge my Absolute Authority I will attack, insult, and humiliate you in this public forum." 

Codes are for sissies. I violated two codes already today and it’s not even 10 o’clock. 😀

Besides, why would removing the shielding help the sound? Maybe you need a little more coffee this morning. 😳

Right. I can see how removing the shielding from your breaker panel by opening the door can really help. Not to mention the building codes you're violating........

Things are a whole lot worse than you guys think. Simply removing or even just opening the steel door of the breaker box improves the sound considerable for any system, whether it be high-end, low-end or in-betweener. No jumping up and down and ranting can change reality.

What power cords have you tried 1988 eldorado? 

They're way ahead of you. If you bother to read up on the threads you'll find much better breaker boxes, installations, outlets,......

If you buy into this nonsense then you should start at the breaker box.  Of course, someone will have to market audiophile quality breakers, audiophile romex,  audiophile outlets...

Funny, all this time I thought this thread was about power cords and they sound the way they do rather than digital vs analog and magnets versus phooby dust.  Maybe I need new glasses?

mzkmxcv364 posts01-15-2019 4:20pm@geoffkait

They scored better than the musicians though...

Any song offered in DSD likely has better mastering, so that’s a factor. I also believe that DXD (format used to make DSD) is just a high-rez PCM anyway, and then it’s converted to DSD on export.

>>>>I reckon I’ll file that one under WHATEVER.

A person with general anesthesia, a blind and a deaf person walk into a darkened bar with the music playing loudly and they only serve liquor in small shot glasses....